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Noble Metal-Supported CeO₂ Catalysts for Hydrogen Production via Ethanol Steam Reforming

ChemCatChem 2025年

作者： Silva, Felipe Anchieta e Marques, Eduardo do Espírito Santo Fonseca, Fabio Coral Gurlo, Aleksander Rodrigues, Thenner Silva Nanotechnology Engineering Program Alberto Luiz Coimbra Institute for Graduate Studies and Research in Engineering COPPE Federal University of Rio de Janeiro Av. Horácio Macedo 2030 Rio de Janeiro RJ 21941–972 Brazil Instituto de Pesquisas Energéticas e Nucleares IPEN/CNEN-SP Av. Prof. Lineu Prestes 2242 São Paulo São Paulo 05508-000 Brazil Faculty III Process Sciences Institute of Materials Science and Technology Chair of Advanced Ceramic Materials Technische Universität Berlin Straße des 17. Juni 135 Berlin 10623 Germany

This study investigates the synthesis, characterization, and catalytic performance of noble metal-supported cerium oxide (M/CeO2, where M = Au, Pd, Pt, Rh, Ru) catalysts for ethanol steam reforming, a promis... 详细信息

This study investigates the synthesis, characterization, and catalytic performance of noble metal-supported cerium oxide (M/CeO₂, where M = Au, Pd, Pt, Rh, Ru) catalysts for ethanol steam reforming, a promising method for sustainable hydrogen production. A urea-assisted deposition approach was employed to deposit noble metal nanoparticles uniformly on CeO₂ without stabilizers, preserving the support's crystallinity and enhancing reducibility through strong metal-support interactions. Catalytic tests at 550 °C over 24 h revealed significant differences in activity and the products distribution based on the metal used. Rh/CeO₂ demonstrated the highest performance, achieving complete ethanol conversion and 37.75% hydrogen production, attributed to its efficient C─C and C─H bond cleavage. Pt/CeO₂ and Ru/CeO₂ also displayed high activity and stability, whereas Pd/CeO₂ and Au/CeO₂ primarily produced acetaldehyde due to preferential C─H bond scission. Post-reaction analysis confirmed minimal carbon deposition across all catalysts, with Rh/CeO₂ exhibiting the highest resistance to coke formation. These findings emphasize the importance of noble metal choice and metal-support interactions in optimizing catalyst performance. Rh, Pt, and Ru emerged as the most promising candidates for efficient hydrogen production. This study develops advanced catalysts optimized for renewable energy use for hydrogen production via ethanol steam reforming. © 2025 Wiley-VCH GmbH.

关键词： Catalytic activity and stability Cerium oxide support Ethanol steam reforming Hydrogen production Noble metal catalysts

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Structural distortions in rare-earth transition-metal oxide perovskites under high pressure

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Physical Review B 2020年第22期101卷 224104-224104页

作者： J.-S. Zhou Materials Science and Engineering Program Mechanical Engineering University of Texas at Austin Austin Texas 78712 USA

Owing to their structural complexity and wide range of possible chemical combinations, perovskite oxides exhibit many technically important physical properties. Pressure is a thermodynamic parameter which is useful for tuning physical properties; however, the response of the complex crystal structure to high pressure has not been thoroughly studied and rationalized. This study focuses on in situ high-pressure x-ray diffraction of the orthorhombic perovskite oxides A3+B3+O3, commonly found for the rare-earth transition-metal oxides of the RMO3 formula. Each of the four families of RMO3 (M=Ti, Cr, Mn, Fe) perovskites in this study all crystallize in the same orthorhombic perovskite structure with the Pbnm space group. The lanthanide contraction in these materials leads to varying degrees of orthorhombic distortions that are primarily associated with octahedral site rotations. The pressure-induced change of the lattice parameters demonstrates an evolution from a suppression to an enlargement of the orthorhombic distortion for substitution of the rare-earth element from R=La to Lu in RMO3 perovskites. This unusual crossover of the lattice parameters’ dependence on pressure contradict the results from first-principles calculation but can be rationalized by the intrinsic distortion of the perovskite structure.

关键词： Pressure effects Structural properties Perovskites Transition metal oxides X-ray diffraction

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Valence bond structure of Ta-W alloys

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Acta Metallurgica Sinica(English Letters) 2009年第4期22卷 275-283页

作者： Xiaobo LI Youqing XIE School of Mechanical Engineering Xiangtan University Xiangtan 411105 China Key Laboratory of Materials Design and Preparation Technology of Hunan Province Xiangtan University Xiangtan 411105 China School of Material Science and Engineering Central South University Changsha 410083 China

The valence bond structure of substitutional BCC based Ta-W alloys is studied using characteristic crystal （CC） theory. This theory is based on cluster statistics of random alloys. By studying the correlativity between energy and volume of the CC in Ta- W alloys, the valence bond structure of CC is determined by the energy and shape method. Then, following additive law of CC, the valence bond structure of Ta-W alloys is calculated. It is found that the outer shell valence electronic distribution of Ta-W Mloys shows a continuous change in the whole composition range. The covalent electrons ec （dc, sc, and pc） increase, whereas near free electrons ef decrease with increasing W concentration. The bond length and single-bond radius decrease, whereas bond energy and bond valence increase with increasing W concentration. The mechanism of solid solution strengthening of Ta-W alloys is analyzed based on their valence bond structure.

关键词： Valence bond structure Ta-W alloys

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Drowning in Method, Thirsty for Values: A Call for Cultural Inquiry

Drowning in Method, Thirsty for Values: A Call for Cultural ...

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IEEE Frontiers in Education Conference 2008

作者： Stolk, Jonathan Somerville, Mark Chachra, Debbie Franklin W. Olin College of Engineering United States Department of Mechanical Engineering and Materials Science Franklin W. Olin College of Engineering United States Department of Electrical Engineering and Physics Franklin W. Olin College of Engineering United States Department of Materials Science Franklin W. Olin College of Engineering United States

ISBN: (纸本)9781424419692

A decade or more has passed since publication of most calls for reform in engineering education. In the ensuing time, there has been significant work on the design, implementation, and transferability of appropriate methods and techniques - accompanied by, in most cases, little discussion of the values and beliefs of the people involved. But many theories of change rely on a fundamental shift in human beliefs and values, and purport that institutionalization of methods is impossible without this shift. Given this, now may be a reasonable time to re-visit the questions: What are the values of people involved in engineering education, and are our educational reform efforts considering these values throughout the curriculum design process? In this paper, we examine several models for engineering educational reform, with a particular focus on the role of individual values in determining responses to change. We highlight the importance of developing understandings of individual perspectives and social context. We contrast a user-oriented approach to curriculum design with common scenarios of curriculum design practice, and we argue that, in many cases, successes in curricular change can be traced to employment of user-centered approaches.

关键词： curriculum educational reform user-oriented design values

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Hierarchical microstructure enables high strength and good ductility in as-cast Fe_(27)Ni_(35)Cr_(18.25)Al_(13.75)Co_(2)Ti_(2)Mo_(2) high-entropy alloy

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Journal of materials science & Technology 2024年第12期179卷 9-21页

作者： Jiacheng Niu Zhiqiang Fu Weiping Chen Tiwen Lu Liangyan Hao Wei Xiong Haiming Wen Guangdong Key Laboratory for Advanced Metallic Materials Processing South China University of TechnologyGuangzhou 510640China National Engineering Research Center of Near-net-shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China Key Laboratory of Pressure Systems and Safety Ministry of EducationEast China University of Science and TechnologyShanghai 200237China Physical Metallurgy and Materials Design Laboratory Department of Mechanical Engineering and Materials ScienceUniversity of PittsburghPittsburghPA15261United States of America Department of Materials Science and Engineering Missouri University of Science and TechnologyRollaMissouri 65409United States of America

As-cast alloys often require complex thermomechanical processing to obtain a hierarchical structure to achieve a good combination of strength and *** in this work,a novel hierarchical Fe_(27)Ni_(35)Cr_(18.25)Al_(13.75)Co_(2)Ti_(2)Mo_(2) high-entropy alloy(HEA)with ultra-high tensile strength and excellent ductility was fabricated by direct *** as-cast alloy exhibits hierarchical structure with an ul-trafine lamellar microstructure(ULM),ultrafine rhombus microstructure(URM),ultrafine vermicular mi-crostructure(UVM),nanosized precipitates and spinodal decomposition(SP)that develops during casting and *** incompatibility of face-centered cubic(FCC)and body-centered cubic(BCC)phases in the deformation process leads to heterogeneous deformation-induced(HDI)hardening,which brings the alloy a tensile yield strength(YS)of~1056 MPa,an ultimate tensile strength(UTS)of~1526 MPa and a total elongation(El)of~15.6%.Additionally,the numerous interfaces generated by the hierarchical structure absorb the energy during deformation,effectively retarding the dislocation motion and causing strong work-hardening.

关键词： Direct casting High-entropy alloy Hierarchical microstructure mechanical properties

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Effect of Preparation Methods on mechanical Properties of PVA/HA Composite Hydrogel

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Journal of Bionic engineering 2010年第3期7卷 235-243页

作者： Dekun Zhang~1, Junjie Duan~1, Dagang Wang~2, Shirong Ge~2 1. School of materials science and engineering, China University of Mining and Technology Xuzhou 221116, P. R. China 2. School of mechanical and Electrical engineering, China University of Mining and Technology, Xuzhou 221116, P. R. China [a] School of Materials Science Engineering China University of Mining Technology Xuzhou 221116 P. R. China [b] School of Mechanical Electrical Engineering China University of Mining Technology Xuzhou 221116 P. R. China

Poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) composite hydrogel specimens were prepared with 15% PVA and 1%,2%, 3%, 4% and 5% HA by repeated freezing-thawing. The tests of static and dynamic mechanical properties were carried out todiscuss the influence of different contents of HA and freezing-thawing cycles on the mechanical properties of PVA/HA compositehydrogel. The results of static mechanical tests showed that the PVA/HA composite hydrogel with 3% HA and ninefreezing-thawing cycles had excellent stress relaxation properties, higher relaxation ratio, lower stress equilibrium value andpresented better properties of creep and recovery. The results of dynamic mechanical test showed that the PVA/HA compositehydrogel with nine freezing-thawing cycles had higher storage modulus and loss modulus, so was the PVA/HA compositehydrogel with 3% HA.

关键词： composite hydrogel HA contents freezing-thawing cycles static properties dynamic properties

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Caterpillar-like 3D graphene nanoscrolls@CNTs hybrids decorated with Co-doped MoSe_(2)nanosheets for electrocatalytic hydrogen evolution

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Journal of materials science & Technology 2023年第5期136卷 43-53页

作者： Hao Luo Hongfei Gao Xudong Zhang Fan Yang Chen Liu Kewei Xu Dagang Guo State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Center for High Performance Computing Network Information CenterXi’an Jiaotong UniversityXi’an 710049China

Hydrogen is a clean and flexible energy carrier that has the promising to satisfy urgent demands of the energy crisis and environmental *** hydrogen evolution reaction(HER),a critical half-reaction in water splitting,is one of the greenest and most common methods to obtain high-purity *** preeminent activity and stability electrocatalysts for hydrogen precipitation reac-tion(HER)to reduce energy consumption is of great essential.3D carbon-based materials have attracted widespread concern as the potential scaffolds of highly active and durable electrocatalysts for *** boost the HER activity and prolong the lifespan of electrocatalysts,multifarious 3D carbon architectures make an appearance to be engineered for accelerating electronic/mass transfer and maximizing the expo-sure of active ***,we designed and fabricated high-performance electrocatalysts based on a spe-cial caterpillar-like 3D graphene nanoscrolls@CNTs(GNS@CNTs)scaffold decorated with Co-doped MoSe_(2)nanosheets for *** the caterpillar-like hierarchical structure,CNTs were seamlessly co-bonded and dilated the interlayer and outer spacing of GNS through CVD growth technology,and nickel nanoparticles were covered by the CNTs *** advantage of the plentiful hierarchical pore,larger specific surface area,and higher chemical stability of the caterpillar-like structure,the catalysts exhibited enhanced elec-trocatalytic properties than some existing data *** functional theory calculations showed that the encapsulated nickel nanoparticle could tune the electronic structure of the outer anchored Co-doped MoSe_(2)and optimize itsG of H∗adsorption by electron traversing effect and doping *** indicate that caterpillar-like GNS@CNT is an ideal scaffold f or anchoring actives substance and is suit-able for high-efficient *** study provides new insights for designing hierarchical carbon composite nanostructures for catalysts,sensors,

关键词： Electron traversing effect 3D graphene Graphene nanoscrolls CNT MoSe_(2),Hydrogen evolution reaction

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Weak ferromagnetism in perovskite oxides

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Physical Review B 2020年第10期102卷 104420-104420页

作者： J.-S. Zhou L. G. Marshall Z.-Y. Li X. Li J.-M. He Materials Science and Engineering Program Mechanical Engineering The University of Texas at Austin Austin Texas 78712 USA

Weak ferromagnetism has been widely found in antiferromagnetic systems, including the technically important orthorhombic perovskites RFeO3 (R=rareearth) owing to spin canting associated with crystal symmetry. Antisymmetric exchange interaction (AEI) and single-ion anisotropy (SIA) are the essential mechanisms responsible for the development of noncollinear structures in antiferromagnetic systems. AEI and SIA share the same structural restriction to facilitate the spin canting. While both AEI and SIA originate from the spin-orbit coupling effect, they have sharply different dependences on the local structure. Consideration of the structural dependence of a canted spin motivates us to revisit the orthoferrite family. The spin canting along the c axis measured on precisely oriented crystals increases monotonically from LaFeO3 to LuFeO3. Based on Moriya's model, AEI is sensitive to the octahedral-site distortion in the perovskite structure. However, the site distortion does not exhibit a monotonic change with the rare-earth substitution. Instead, a linear relationship has been found in both the octahedral rotation and the spin canting angle versus the rare-earth ionic radius, which indicates that SIA plays a significant role leading the spin canting in orthoferrites.

关键词： Dzyaloshinskii-Moriya interaction Ferromagnetism Magnetic order Ferrites Perovskites

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Carbon-based flexible self-supporting cathode for lithium-sulfur batteries:Progress and perspective

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Carbon Energy 2021年第2期3卷 271-302页

作者： Qinghuiqiang Xiao Jinlin Yang Xiaodong Wang Yirui Deng Peng Han Ning Yuan Lei Zhang Ming Feng Chang‐an Wang Ruiping Liu Department of Materials Science and Engineering China University of Mining and Technology(Beijing)BeijingChina School of Materials Science and Engineering Tsinghua UniversityBeijingChina Department of Mechanical Engineering University of Alaska FairbanksFairbanksAlaskaUSA Department of Applied Physics Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of EducationJilin Normal UniversityChangchunChina

The flexible self-supporting electrode can maintain good mechanical and electrical properties while retaining high specific capacity,which meets the requirements of flexible ***-sulfur batteries(LSBs),as a new generation of energy storage system,hold much higher theoretical energy density than traditional batteries,and they have attracted extensive attention from both the academic and industrial *** of a proper substrate material is important for the flexible self-supporting *** materials,with the advantages of light weight,high conductivity,strong structural plasticity,and low cost,provide the electrode with a large loading space for the active material and a conductive *** makes the carbon materials meet the mechanical and electrochemical requirements of flexible *** this paper,the commonly used fabrication methods and recent research progresses of the flexible self-supporting cathode with a carbon material as the substrate are *** sulfur loading methods are summarized,which provides useful information for the structural design of the *** the first review article of the carbon-based flexible self-supporting LSB cathodes,it provides valuable guidance for the researchers working in the field of LSB.

关键词： carbon flexible lithium sulfur batteries self-supporting

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The journey of multifunctional bone scaffolds fabricated from traditional toward modern techniques

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Bio-Design and Manufacturing 2020年第4期3卷 281-306页

作者： Ashkan Bigham Firoozeh Foroughi Erfan Rezvani Ghomi Mohammad Rafienia Rasoul Esmaeely Neisiany Seeram Ramakrishna Department of Biomaterials Tissue Engineering and NanotechnologySchool of Advanced Technologies in Medicine(ATiM)Isfahan University of Medical SciencesIsfahanIran Department of Materials Science and Engineering Faculty of EngineeringNational University of Singapore9 Engineering Drive 1Singapore 117576Singapore Department of Mechanical Engineering Center for Nanofibers and NanotechnologyNational University of SingaporeSingapore 119260Singapore Biosensor Research Center Isfahan University of Medical SciencesIsfahanIran Department of Materials and Polymer Engineering Faculty of EngineeringHakim Sabzevari University*** SabzevarIran

As a bone scaffold,meeting all basic requirements besides dealing with other bone-related issues-bone cancer and accelerated regeneration-is not expected from traditional scaffolds,but a newer class of scaffolds called *** a clinical point of view,being a multifunctional scaffold means reducing in healing time,direct costs-medicine,surgery,and hospitalization-and indirect costs-loss of mobility,losing job,and *** main aim of the present review is following the multifunctional bone scaffolds trend to deal with both bone regeneration and cancer *** consideration is given to different fabrication techniques which have been applied to yield these materials spanning from traditional to modern ***,the hierarchical structure of bone plus bone cancers and available medicines to them are introduced to familiarize the potential reader of review with the pluri-disciplinary essence of the ***,a brief discussion relating to the future trend of these materials is provided.

关键词： Multifunctional scaffolds Bone cancer Fabrication techniques Bone tissue regeneration

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